Publication Date:
1994-08-12
Description:
The folding pathways of large, highly structured RNA molecules are largely unexplored. Insight into both the kinetics of folding and the presence of intermediates was provided in a study of the Mg(2+)-induced folding of the Tetrahymena ribozyme by hybridization of complementary oligodeoxynucleotide probes. This RNA folds via a complex mechanism involving both Mg(2+)-dependent and Mg(2+)-independent steps. A hierarchical model for the folding pathway is proposed in which formation of one helical domain (P4-P6) precedes that of a second helical domain (P3-P7). The overall rate-limiting step is formation of P3-P7, and takes place with an observed rate constant of 0.72 +/- 0.14 minute-1. The folding mechanism of large RNAs appears similar to that of many multidomain proteins in that formation of independently stable substructures precedes their association into the final conformation.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Zarrinkar, P P -- Williamson, J R -- New York, N.Y. -- Science. 1994 Aug 12;265(5174):918-24.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Chemistry, Massachusetts Institute of Technology, Cambridge 02139.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/8052848" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Base Sequence
;
Introns
;
Kinetics
;
Magnesium/metabolism/pharmacology
;
Models, Chemical
;
Molecular Sequence Data
;
*Nucleic Acid Conformation
;
Nucleic Acid Hybridization
;
Oligonucleotide Probes
;
RNA, Catalytic/*chemistry/metabolism
;
RNA, Protozoan/*chemistry
;
Ribonuclease H/metabolism
;
Temperature
;
Tetrahymena/*genetics
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics